How to Configure Multiple Area in .NET Core 3.x

Question

I have multiple numbers of Areas in me project. After upgrading project form .NET Core 2.2 to 3.1 those Areas aren't work/call.

My Controller inside Area looks like: -

[Area(nameof(CRM))]
[Authorize]
[ServiceFilter(typeof(ActionFilter))]
public class DefaultController : Controller
{
    public IActionResult Index()
    {
        return View();
    }
}

And the previous configurations for handling multiple Area looks like below: -

   routes.MapRoute(name: "Area", template: "{area:exists}/{controller=Default}/{action=Index}/{id?}");
   routes.MapRoute(name: "Area Default Create", template: "{area:exists}/{controller=Default}/create", defaults: new { action = "CreateOrEdit" });
   routes.MapRoute(name: "Area Default Edit", template: "{area:exists}/{controller=Default}/edit/{id}", defaults: new { action = "CreateOrEdit" });

As we have to use UseEndpoints in .NET Core 3.1 and the new Configuration for handling Multiple-Area is likes below [What I was tried]

Reference # Endpoint Routing .net core 3-Multiple Areas & https://aregcode.com/blog/2019/dotnetcore-understanding-aspnet-endpoint-routing/

endpoints.MapControllerRoute(name: "areas", pattern: "{area}/{controller}/{action=Index}/{id?}");

But, It isn't works also try to call by below way & not succeed: -

endpoints.MapAreaControllerRoute(name: "Area", areaName: "areas", pattern: "{area:exists}/{controller=Default}/{action=Index}/{id?}");
endpoints.MapAreaControllerRoute(name: "Area Default Create", areaName: "areas", pattern: "{area:exists}/{controller=Default}/create", defaults: new { action = "CreateOrEdit" });
endpoints.MapAreaControllerRoute(name: "Area Default Edit", areaName: "areas", pattern: "{area:exists}/{controller=Default}/edit/{id}", defaults: new { action = "CreateOrEdit" });

Even it's not working for individual Area too

Reference# https://learn.microsoft.com/en-us/aspnet/core/migration/22-to-30?view=aspnetcore-3.1&tabs=visual-studio

endpoints.MapAreaControllerRoute(name: "Area", areaName: "CRM", pattern: "CRM/{controller=Default}/{action=Index}/{id?}");

Answer 1

I just solve the problem by myself and here is the solution for overcoming this situation: -

In Startup.cs class add below line for handling dynamic route for multiple Areas

endpoints.MapAreaControllerRoute(name: "areas", "areas", pattern: "{area:exists}/{controller=Default}/{action=Index}/{id?}");  

Here areas is the name of your Areas folder [Default]. You can change it as your wish.

Change the header markup of controllers likes below: -

[Area(nameof(CRM))]  // CRM is the another-folder name inside Areas folder
[Route("CRM/[controller]/[action]")]
[Authorize]
[ServiceFilter(typeof(ActionFilter))]
public class DefaultController : Controller
{
    public IActionResult Index()
    {
        return View();
    }
}

Finally change your Razor markup likes below to call your target Action inside Controller of Areas folder

<a asp-area="CRM" asp-controller="Default" asp-action="Index">Home of CRM</a>